- Email: [email protected]
Ovarian tumors in the quahog Mercenaria mercenaria
JOURNAL
OF
INVERTEBRATE
Ovarian
PATHOLOGY
Tumors
14, 266-267
(
in the Quahog
The occurrence of tumors in invertebrates has been reviewed by B. Scharrer and M. Lockhead (Cancer Res., 10,403-419,1950) and in mollusks, more recently, by G. B. Pauley (I. Natl. Cancer Inst. Monograph No. 31, in press). The majority of these tumolrs have b’een observed a’s single occurrences. According to these reviews there are no reports of tumors in the quahog Mercenariu mercenaria. We have observed three cases of neoplasia in quahog ovaries during the routine histopathologic examination of 1,300 M. mercenaria. All of the animals were collected from Narragansett Bay, Rhode Island, during the summer of 1968. In no case did the animals show any unusual gross morphologic anomalies. The animals were sacrificed and potted in toto in Zenker’s solution made with a zinc chloride base. After 15 min of fixation, multiple sections were taken and fixed overnight. The sections were then trimmed to a thickness of 3.0 mm, put into receptacles, and washed in running tap water for 8 hr. Tissues were cleared in dioxane and embedded in Pamplast (M.P. S6”C), cut at 6 p, and stained with Harris’s hematoxylin and eosin. Coronal sections of the animals revealed a proliferation of the germinal epithelium into the lumina of the follicles ( Fig. 1) . In most areas the normal ovarian follicles (Fig. 2) were completely replaced by large polyhedral cells containing vesicular nuclei with a clear pink cytoplasm (Fig. 3). Many of the nuclei contained prominent redstaining nucleoli with clumping of the chromatin material at the periphery of the nucleus. An infiltration of smaller hyperchromatic nuclei (Fig. 4) were scattered throughout the tumor. Many of the islands
1969)
Mercenaria
mercenuria
of tumor cells contained a core of deep pink-staining fibrous connective tissue with some necrosis (Fig. 4, arrow), while in other parts of the tumor small cystic spaces could be seen. Mitotic figures were scattered throughout the tumor masses. In one of the three animals, early invasion was seen in the kidney area where definite clumps of tumor cells appeared in the supporting connective tissue (Fig. 5). Microscopically this tumor is similar to the granulosa-cell carcinoma of the ovary in the human female. G. B. Pauley and C. S. Sayce (J. Invertebrate Pathol., 10, 1-8, 1968) described a benign fibrous tumor in a Pacific oyster (Crassostrea gigas) which may have been of myogenic or gonadal origin. The present observations in M. mercenaria appear to be the first report of a primary ovarian tumor in molluscs. Additional samples are being collected from two sites where tumor-bearing quahogs were previously found. Histopathologic examination of samples from locations found to be free of tumorous animals will also be made. Distributions of affected animals may then be better understood. At this time there is no apparent relationship between incidence of tumorous quahogs and water quality. PAUL P. YEVICH' MARCIA M. BERRY~
National Marine Water Quality Laboratory P. 0. Box 277 West Kingston, Rhode Zsland 02892 Received April 18, 1969 1 The authors thank Drs. George W. Anderson and James W. Mold, Pathologists, at the Providence Lying-In Hospital for assistance in the diagnosis of the tumor, and Mrs. Betty J. Arnold for the tissue preparation.
NOTES
Sections of the ovary Proliferation of germinal ovarian follicles. FIG. High power of Fig. 3 infiltration with deeply 750 X. FIG. 5. Mass of glandular mass of the
267
of Mercenaria mercenaria; stained with Harris’s hematoxylin and eosin. FIG. 1. epithelium into the lumen of the follicle (arrow). 1875 X . FIG. 2. Normal 3. Ovarian follicles filled with masses of tumor cells (arrow). 295 X. FIG. 4. showing tumor mass with large polyhedral cells bearing vesicular nuclei and stained hyperchromatic nuclei. Pink-stained necrotic area can be noticed (arrow). tumor cells lying in the connective tissue between the pericardial funnel and the kidney. 295X.
OF
INVERTEBRATE
Ovarian
PATHOLOGY
Tumors
14, 266-267
(
in the Quahog
The occurrence of tumors in invertebrates has been reviewed by B. Scharrer and M. Lockhead (Cancer Res., 10,403-419,1950) and in mollusks, more recently, by G. B. Pauley (I. Natl. Cancer Inst. Monograph No. 31, in press). The majority of these tumolrs have b’een observed a’s single occurrences. According to these reviews there are no reports of tumors in the quahog Mercenariu mercenaria. We have observed three cases of neoplasia in quahog ovaries during the routine histopathologic examination of 1,300 M. mercenaria. All of the animals were collected from Narragansett Bay, Rhode Island, during the summer of 1968. In no case did the animals show any unusual gross morphologic anomalies. The animals were sacrificed and potted in toto in Zenker’s solution made with a zinc chloride base. After 15 min of fixation, multiple sections were taken and fixed overnight. The sections were then trimmed to a thickness of 3.0 mm, put into receptacles, and washed in running tap water for 8 hr. Tissues were cleared in dioxane and embedded in Pamplast (M.P. S6”C), cut at 6 p, and stained with Harris’s hematoxylin and eosin. Coronal sections of the animals revealed a proliferation of the germinal epithelium into the lumina of the follicles ( Fig. 1) . In most areas the normal ovarian follicles (Fig. 2) were completely replaced by large polyhedral cells containing vesicular nuclei with a clear pink cytoplasm (Fig. 3). Many of the nuclei contained prominent redstaining nucleoli with clumping of the chromatin material at the periphery of the nucleus. An infiltration of smaller hyperchromatic nuclei (Fig. 4) were scattered throughout the tumor. Many of the islands
1969)
Mercenaria
mercenuria
of tumor cells contained a core of deep pink-staining fibrous connective tissue with some necrosis (Fig. 4, arrow), while in other parts of the tumor small cystic spaces could be seen. Mitotic figures were scattered throughout the tumor masses. In one of the three animals, early invasion was seen in the kidney area where definite clumps of tumor cells appeared in the supporting connective tissue (Fig. 5). Microscopically this tumor is similar to the granulosa-cell carcinoma of the ovary in the human female. G. B. Pauley and C. S. Sayce (J. Invertebrate Pathol., 10, 1-8, 1968) described a benign fibrous tumor in a Pacific oyster (Crassostrea gigas) which may have been of myogenic or gonadal origin. The present observations in M. mercenaria appear to be the first report of a primary ovarian tumor in molluscs. Additional samples are being collected from two sites where tumor-bearing quahogs were previously found. Histopathologic examination of samples from locations found to be free of tumorous animals will also be made. Distributions of affected animals may then be better understood. At this time there is no apparent relationship between incidence of tumorous quahogs and water quality. PAUL P. YEVICH' MARCIA M. BERRY~
National Marine Water Quality Laboratory P. 0. Box 277 West Kingston, Rhode Zsland 02892 Received April 18, 1969 1 The authors thank Drs. George W. Anderson and James W. Mold, Pathologists, at the Providence Lying-In Hospital for assistance in the diagnosis of the tumor, and Mrs. Betty J. Arnold for the tissue preparation.
NOTES
Sections of the ovary Proliferation of germinal ovarian follicles. FIG. High power of Fig. 3 infiltration with deeply 750 X. FIG. 5. Mass of glandular mass of the
267
of Mercenaria mercenaria; stained with Harris’s hematoxylin and eosin. FIG. 1. epithelium into the lumen of the follicle (arrow). 1875 X . FIG. 2. Normal 3. Ovarian follicles filled with masses of tumor cells (arrow). 295 X. FIG. 4. showing tumor mass with large polyhedral cells bearing vesicular nuclei and stained hyperchromatic nuclei. Pink-stained necrotic area can be noticed (arrow). tumor cells lying in the connective tissue between the pericardial funnel and the kidney. 295X.